Figure 16. November 14, 1996 A. meridian scanning photometer record from Poker Flat. The top record is for the 4861 Å Hb line of atomic hydrogen. The second line is the fast 4278 Å line of nitrogen and the bottom trace is for the 5577 Å line of atomic oxygen. (Poker Flat MSP  archives)
Figure 17

Section 4.1

Contents